Railway switch operating apparatus



Dec. 12, 1939. w, c McwHlRTER AL 2,183,164

RAILWAY SWITCH OPERATING APPARATUS Filed June 17, 1937 9 Sheets-Sheet 1 THEIR ATTORN EY 9 SheetsSheet 2 TIIEIH ATTORN EY Dec. 12, 1939. w. c. M WHIRTER ET AL RAILWAY SWITCH OPERATING APPARATUS Filed June 17, 1937 Dec. 12, 1939. w. c M WHIRTER ET AL 2,183,

RAILWAY SWITCH OPERATING APPAfiATUS Filed June 17, 1937 9 Sheets-Sheet 3 n [I 4 55; E

mm K mm E km mmb mm I INVENTORS willa'am CMQUhzfzep and BY E 12 GLZZLZQ.

THEIR ATTORNEY Dec. 12, 1939. I

W. C. M WHIRTER ET AL RAILWAY SWITCH OPERATING APPARATUS Filed June 17 1957 9 Sheets-Sheet 4 INVEN:TOR5 (0661mm 6'. MQCUhLPeP and BY G-LZZL ZQ.

THEIR ATTORNEY Dec; 1939- w. c. MGWHIRTER El AL 2,183,164

RAILWAY SWITCH OPERATING APPARATUS Filed June 17, 1937 9 Sheets-Sheet 5 m Fig. 7. Z 29 d 14 V 22 21 92 H7 25 28 291 26 119 1113 6 292 97 D H "4 112 112 91 2 11 135 I 11? I 298 94 9 95 124 L 1, i i 0 E L I I I A l INVENTORS LUzZZzamC.MQLU/umep and Hg 8 BY Ed G.LL Zfl THEIR ATTORNEY 9 Sheets-Sheet 6 THEIR ATTORNEY W. c-M wHlRTER ET AL RAILWAY SWITCH OPERATING APPARATUS Filed June 1'7, 1937 Dec. 12, 1939.

w. c. M WHIRTER ET AL 2,183,164

RAILWAY SWITCH OPERATING APPARATUS Filed June 17, 1937 9 SheetsSheet 7 n. a s u TMG Qm E M e THL 'IR ATTORN EY Dec. 12, 1939. w, c McWHlRTER r AL 2,183,164

RAILWAY SWITCH OPERATING APPARATUS Filed June 17, 1937 9 Sheets-Sheet 8 501 a 5L L g 305 I r F I I I90 501 I H u.-

INVENTQR \nml I l, LULZlzamC/ElU/m" Pram THE/H ATTORNEY Dec. 12, 1939. w, c McwHlRTER AL 2,183,164.

RAILWAY SWITCH OPERATING APPARATUS Fil'ed June 17, 1957 9 Sheets-Sheet 9 0 F5 29 mg 556 559 Q Q INVENTORS 50. wzzzm CMQU/zzhep 3H 255 and Ed G.Lz'zzle.

THEIR ATTORNEY Patented Dec. 12, 1939 UNITED STATEfi *GFHQE William C. McWhirter and Edwin G.

assignors Wilkinsbnrg, Pa.,

Little,

to iihe Union Switch & Signal Company, Swissvale, Fa, a corporation of Pennsylvania Application June 17, 1937, Serial No. 148,706

27 Claims.

Our invention relates to railway switch operating apparatus.

One object of our invention is the provision of an efiicient and improved mechanism for operating and looking a railway switch, to meet the requirements of heavier track equipment and rolling stock.

Another object of our invention is the provision of a novel and improved circuit controller for detecting any failure of the switch points to occupy their proper positions relative to the stock rails in either extreme position of the switch.

Another object of our invention is the provision of a novel and improved latching mechanism which may be incorporated into the circuit controller when desired, and which when utilized, provides means whereby, it the indication contacts of the circuit controller are improperly forced open, as by a train trailing the switch, when the switch points are locked in either extreme position, these contacts will be positively held open by the latching device until the latching device is manually operated to release the contacts.

Another object of our invention is the provision of novel and improved means for permitting manual operation of a power operated switch.

Another object of our invention is the provision, in connection with a switch operating motor, of a novel and improved brake including means for normally biasing the brake to a braking condition, electromagnetic means for releasing the brake when the motor becomes energized, and means for at times manually releasing the brake.

Other objects and characteristic features of our invention will appear as the descrip ion proceeds.

We shall describe two forms of apparatus embodying our invention, and shall then point out the novel features thereof in claims.

In the accompanying drawings, Fig. l is a top plan view showing a frog layout A operated by a switch machine 1v; embodying our invention. Fig. 2 is a top plan view on an enlarged scale of the switch machine M shown in Fig. 1, the covers of the machine being removed to better illustrate the construction and arrangement of the operating mechanism. Fig. 3 is a longitudinal sectional view showing a portion of the operating and locking mechanism of the switch machine illustrated in Fig. 2. Fig. 4 is an enlarged vertical longitudinal sectional view of a portion of the switch machine shown in Fig. 2. Figs. 5 and 6 are detail views showing the operating and looking mechanism illustrated in Fig. 3 in different operating positions. Fig. 7 is a plan view on an enlarged scale of a portion of the operating mechnism of the switch machine shown in Figs. 1, 2, and 3, the cover for the mechanism being removed and certain of the parts being broken away to more clearly illustrate the construction thereof. Fig. 8 is a sectional view taken on the line VIII-47111 of Fig. 7. Fig. 9 is a vertical sectional View or". the clutch mechanism C forming part of the switch machine illustrated in the preceding views. Fig. 10 is a sectional view taken substantially on the line X-X of Fig. 9. Fig. 11 is a bottom view of the gear wheel 91] forming part of the mechanism shown in Figs. '7 and 8. Fig. 12 is a top view of the clutch member I05 forming part of the mechanism shown in Figs. 4, 7, and 8. Fig. 13 is a bottom View of the clutch member I555 shown in Figs. 4, 7, and 8. Fig. 14 is a top view of the gear wheel 65 shown in Figs. 4, '7, and 8. Fig. 15 is an end view of the handthrow and shifter lever mechanism as it appears when viewed from the bottom in Fig. '7. Fig. 16 is a fragmentary vertical sectional view of the motor B and associated brake mechanism forming part of the switch machine shown in Figs. 2 and i. Fig. 1! is a sectional view taken on the line XVII-XVII of Fig. 16. Fig. 18 is a top plan View with cover removed, of the brake mechanism shown in Fig. 16. Fig. 19 is a detail view showing the brush assembly for the motor illustrated in Fig. 16. Fig. 20 is a top plan View showing, on an enlarged scale, a portion of the circuit controller G forming part of the switch machine M illustrated in Figs. 1 and 2. Fig. 21 is a top plan view showing some of the details of construction of the circuit controller G forming part or" the switch machine M. Fig. 22 is a top plan view with the contacts removed, of the circuit controller shown in Figs. 2, 20, and 21. Fig. 23 is an enlarged longitudinal sectional view of the circuit controller G shown in Fig. 2 with certain of the parts removed to better illustrate the construction of the remaining parts. Fig. 24 is an enlarged transverse vertical sectional View of the circuit controller shown in Fig. 2. Fig. 25 is an enlarged end view of a portion of the circuit controller shown in Fig. 2 as it appears when viewed from the left in Fig. 2. Fig. 26 is a top plan view showing a modified form of switch machine embodying my invention. Fig. 27 is a vertical sectional View of the switch machine shown in Fig. 26. Fig. 23 is a detail vertical sectional View of latch mechanism forming part of the modified form of switch machine illustrated in Figs. 26 and 27. 29 is a detail horizontal sectional View of a portion of the latch mechanism forming a part of the modified form of switch machine illustrated in Figs. 26 and 27. Fig. 3611s a detail view showing other latch mechanisms forming part or" the modified form of switch machine illustrated in Figs. 26 and 2'7. Fig. 31 is a detail View showing on an enlarged scale the detector rod H and associated connecting rod Ell forming part of the switch operating apparatus illustrated in Fig. 1.

Similar reference characters refer to similar parts in each of the several views.

Referring first to Fig. 1, the reference character A designates movable point frog, and the reference character M designates a switch machine embodying our invention for operating the frog A.

The frog A is of standard construction, and comprises the usual stock rails RR between which are movabiy mounted two pairs of switch points P P and P P respectively, such pairs being disposed in opposed relation and having their confronting ends connected by front rods l and l respectively. The switch points P P are also connected together by the usual head rod 2 and the switch points P P are similarly connected together by the usual head rod 2 The head rod 2 in turn, is connected through the usual switch basket 3* with one end of a throw rod 41, the other end of which is pivotally connected to one arm 5 of a bell crank lever 5. The bell crank lever 5 is pivotally supported in the trackway at 6, and the other arm 5 thereof is connected, by means of a connecting link i, with the corresponding arm t of a similar bell crank lever 3 which is pivotally supported in the trackway at 9. The remaining arm 8 of hell crank lever 8 is connected, by means of a connecting rod it and a screw jaw m with a throw rod H, which throw rod, in turn, is connected with the head rod 2 by means of a switch basket 3. The throw rod ll extends under one switch point P and the one stock rail R, and is connected at its free end with the longitudinally movable operating rod 0 of the switch machine M. It will be apparent, therefore, from an examination of the drawing that when the operating rod 0 is actuated by the switch machine, the switch points P P and P P will be simultaneously reversed.

The upper ends of the front rods l and l extend underneath the stock rail R and are operatively connected with two lock rods L" and L which. project into the switch machine M. These look rods are of standard construction, and each comprises two longitudinally adjustable bars l2 and i3 arranged side by side. Each bar i2 is provided in its opposite edges with a short notch lfl and a long notch lt and each bar it is similarly provided in its opposite edges with a short notch it and a long notch l3 The two notches in each bar are spaced apart a distance which is substantially equal to the switch stroke, and the bars are so adjusted that the long notch in each bar is disposed directly opposite the short notch in the other contiguous bar.

Referring now to Figs. 2, 3, and l, the switch machine, in the form here illustrated, comprises a suitable casing is consisting of two separate box-like castings H and M secured to a base plate it. The casting Mi is closed at its upper end by removable cover Hi and the casting i i is closed at its upper end by removable covers M and M (see Fig. 1). The base plate M is secured to two adjacent ties at the outer side of the rail l, and formed partly in the base plate and partly in the castings Hi and N are suitable guideways which slidably receive the operatin rod 0 and the two lock rods L and L. Slidably mounted in the base plate l4 directly below the operating rod 0 and the two lock rods L and L and intersecting the operating rod 0 and the two lock rods L and L at right angles, is a slide bar N. Attached to or formed integral with, the upper side of this slide bar near its right-hand end, as viewed in Fig. 3, are three spaced locking dogs 16, ll, and iii, the two outer ones of which it and Ill are in the form of rectangular blocks, and the middle one of which I?! is in the form of a T-shaped block having its upper surface formed with rack teeth for a pur pose which will appear hereinafter. The looking dogs i6, ii, and it are adapted to selectively enter certain ones of the aligned notches in the bars l2 and it to lock the switch points of the movable frog A in their extreme positions in a manner which will be described in detail hereinafter.

For the purpose of actuating the operating rod 0 and the slide bar N to effect their respective operating and locking functions in the intended manner, we provide an operating mechanism comprising a vertically disposed switch actuating shaft the upper end of which is journaled in a ball bearing 2i (see Figs. 4 and 8) disposed in a bearing recess 22 formed in a bearing plate 23, and the lower end of which is journaled in a ball bearing 24 disposed in a bearing recess 25 formed in the bottom wall of the casting M The bearing plate 23 is secured by means of bolts it to lugs it formed on the side walls of the casting M The portion of the shaft which is iournaled in the bearing 2i is reduced in diameter, and interposed between the lower side of the bearing 2! and a shoulder Eli which is formed at the lower end of the reduced portion of the shaft 281 is a thrust washer 28, the function of which will become apparent as the description proceeds. The bearing 2! rests at its underside on a shoulder formed at the bottom of the bearing recess 22, and screwed onto the shaft above the bearing is a nut 29. It will be seen, therefore, that the shaft 28 is suspended from the bearing plate by means of the bearing and the nut 29. The shaft 2E9 is disposed with its axis located at one side of the point of intersection of the operating rod 0 and the slide bar N, and is provided at its lower end with a crank 30 which is formed integrally with the shaft. This crank extends in opposite directions from the shaft, and is provided at one end with a depending pin 3! which carries two rollers 32 and 33, and at the other end with 2. depending pin 34 which carries a roller 35. The roller 32 cooperates with a slot 35 which extends longitudinally of a cross arm 37, formed integrally with the operating rod 0, while the two rollers 33 and 35 cooperate respectively with oppositely disposed arcuate slots 38 and 35-) formed in a motion plate 40 which is secured to the upper side of the slide bar N adjacent its left-hand end. The slot 36 is provided with straight side wall portions 36 and 36 which extend from its medial portions to its right-hand end where these straight side wall portions merge into a curved end portion 36, and with outwardly curved side wall portions 36 and 36 which describe an arc, and which extend from the medial portion of the slot to its left-hand end where these curved side wall portions merge into a curved end portion 35 The confronting ends of each of the two arcuate slots 38 and 39 in the motion plate 40 are formed with relatively short straight parallel portions 38- and 39 and with curved offset portions 38 and 39 The opposite ends of the slots 38 and 39 terminate at their outer sides in straight parallel portions 38 and 39.

The operation, as a whole, of the portion of the switch machine thus far described is as follows: When the operating rod 0 and the slide bar N are in their normal positions in which they are shown in Fig. 3, and the switch points are in their corresponding positions in which they are shown in Fig. 1, the locking dogs l6, l1, and I8 and the lock rods L and L occupy the relative positions in which they are shown in Fig. 3. That is to say, the locking dog It is within the lower pair of notches in the lock rod L and the locking dog I! is within the upper pair of notches in the lock rod L It will be readily understood that under these conditions, any thrust on the switch points tending to move them away from their normal positions, such for example, as a thrust due to an improper trailing move will be resisted by the dogs [6 and H, and it follows, therefore, that the switch points are securely locked in their normal positions by the dogs IE and I1.

When it is desired to reverse the switch points, the shaft is rotated in a clockwise direction to rotate the crank in the same direction. This rotation of the crank 39 causes the roller 33 to engage the arcuate slot 38 at the offset portion 38 whereby the slide bar N is moved toward the right, as viewed in Fig. 3 far enough to withdraw the locking dog l6 from the notches l2 and l3 in the lock rod L the locking dog I! being simultaneously withdrawn from the notches 13 and 12 in the lock rod L thus unlocking the switch points P P and P P During this movement of the crank the roller 32 whose initial position was at the left-hand end of the slot 36 is moved to the medial portion of the slot, or at the junction of the curved and straight walls thereof, but due to the curvature of the upper curved wall 36 this movement of the roller does not cause the operating rod 0 to be moved. It will be seen, therefore, that during the first part of the movement of the crank 30, the slide bar N is moved to unlock the switch points, but

the operating rod 0, and hence the switch points, remain stationary. However, in the continued movement of the crank 30, the roller 32 engages the straight side wall portion 36 of the slot in the operating rod 0 and imparts sufficient movement to the operating rod in the general direction in which the operating rod is being moved to completely reverse the switch points. During the greater part of this portion of the movement of the crank, the roller 33 engages the slot 38 in the motion plate within the curved parallel sides thereof, so that the crank then serves as a locking means for the slide bar N to prevent longitudinal movement of the slide bar. When the switch points have been moved to their midstroke positions, movement of the slide bar N is prevented by engagement of the rollers 33 and 35 with the outer side walls 33 and 39 of the two slots 38 and 39 to hold the slide bar N in its intermediate position in which all of the locking dogs are out of engagement with the associated lock rods, as shown in Fig. 5. The movement of the switch points to their reverse positions moves the lock rods L and L from the relative positions in which they are shown in Fig. 3 to the relative positions in which they are shown in Fig. 6, so that the notches I2 and l3 in the lock rod L are then in alignment with the locking dog I1, and the notches E2 and l3 in the lock rod L are in alignment with the locking dog l 8. Upon further continued rotationof the crank 30, roller 35 moves into engagement with the straight portion 39 of the slot 39 in the motion plate 49, and imparts a second movement to the slide bar N in the same direction as the first movement, this latter movement being sufficient to cause the locking dog I! to enter the notches l2 and l3 in the lock rod L and the dog It to enter the notches N and NF in the lock rod L as shown in Fig. 6, thus locking the switch points in their reverse positions. It should be pointed out that the parts are so proportioned that a sufficient amount of idle travel of the shaft 25 will take place between the time the roller 32 moves out of engagement with the straight side wall portion 33 of the slot 35 and the time the roller 35 moves into engagement with the straight portion 39 of the slot 39 in the motion plate 48 to insure that if the locking dogs I? and 58 are prevented from entering the respective notches in the lock rods L and L for any reason, due for example, to the lock rods being misadjusted or becoming damaged, the switch movement will not become stalled until after the switch points have reached their full reverse positions and are held in these positions by the coaction between the roller 35 and the slot 39 in the motion plate 43. It should also be pointed out that when the switch points are locked in their reverse positions, any thrust tending to open the points is then taken by the locking dogs I! and it, thus insuring an effective locking of the switch points under these conditions. It will be noted from the foregoing that the movement of the operating rod which reverses the switch points is subsequent to the initial movement of the slide bar which unlocks the switch points, but in advance of the final movement of the slide bar which looks the switch points in their reverse positions.

In order to restore the switch points to their normal positions after they have been reversed, as above described, the shaft 29 is rotated in a counterclockwise direction to rotate the crank 30 in this direction. The subsequent movements of the operating rod and slide bar above described are maintained under these conditions, but the directions of the movements are reversed.

A main spur gear (see Figs. 4, 7, and 8) is mounted for rotation coaxially with the switch I actuating shaft 29, and is formed with a hub 46 which extends into the bearing recess 25 and cooperates with the upper side of the ball bearing 24 to prevent longitudinal displacement of the spur gear in response to a downward thrust which is at times exerted. on this gear in a manner which will appear hereinafter. The gear 45 is driven, th ough the medium of a train of gears and a friction clutch C, by a motor B which is bolted to the casting M at the left-hand end of the casting. The train of gears in the form here shown comprises a pinion M which is formed integrally with a vertical shaft 38, and which drives the spur gear 45. The vertical shaft 48 is journaled at its lower end in a bearing sleeve 49 mounted in a bearing opening 53 formed in the bottom wall of the casting M and at its upper end in a bearing sleeve 5! mounted in a bearing opening 52 formed in a bearing plate 53 which is bolted to suitable supports provided on the casting I4 The shaft 48 is driven by a spur gear 54 which is splined to the shaft 48 above the pinion 4?, and which meshes with another spur gear 55 splined to a second vertical shaft 56. This latter vertical shaft is journaled at its lower end in a bearing sleeve 51 mounted in a bearing opening 58 formed in the bottom wall of the casting 14 and at its upper end in a bearing sleeve 59 mounted in a bearing opening 60 formed in the bearing plate 53, and has secured thereto a spur gear 66 which is driven by a pinion 5| keyed to a third vertical shaft 52 by means of a feather key 62 (see Fig. 9). The reduction gearing also comprises a bevel gear 63 which meshes with a bevel pinion 64 keyed to the armature shaft 65 of the motor B.

The vertical shaft 62 supports the friction clutch C, and is rotatably mounted at its lower end within the hub of the bevel gear 63 (see Fig. 9). The hub of the bevel gear 63, in turn, is provided With a depending portion which projects into a ball bearing 66 that is disposed in a bearing recess B'I formed in the bottom wall of the casting M whereby the bevel gear is rotatably mounted in the bottom of the casting M The upper end of the shaft 62 is threaded to receive a vertically adjustable bearing sleeve 68, and mounted on this bearing sleeve is a ball bearing 69 which fits loosely Within a bearing opening I0 formed in the bearing plate 53. Secured to the bearing plate 53 above the bearing 69 is a plate II which serves to retain grease in the bearing 69. The upper end of the bearing sleeve 69 is provided with a polygonal flange to enable this sleeve to be gripped by a wrench or other suitable tool to facilitate adjusting this sleeve.

The friction clutch C comprises a circular housing I5 which surrounds the shaft 62 in concentric relation thereto between the bevel gear 63 and a clutch plate "I6 that is formed integrally with the hub of the pinion RH, and which is secured at its lower end to the bevel gear 63 to rotate therewith by means of cap screws TI. The hub of the pinion GI extends downwardly beyond the clutch plate '56, and the portion of the hub which is disposed below the clutch plate is formed with a square outer surface. Surrounding this square portion of the hub in superposed concentric relation are a clutch facing I9, a driving plate I8, a clutch facing I9, a clutch plate 89, a clutch facing I9, a driving plate 8i, a clutch facing 19, and a clutch plate 82. The driving plates I8 and are free to both rotate and move vertically with respect to the square portion of the hub of the pinion 6i, and are also free to move vertically with respect to the clutch housing I5, but are constrained to rotate in response to rotation of the clutch housing by means of diametrically opposite protruding ears fil and Bi which project with some clearance into vertically disposed channels or offset portions 15 formed in the opposite sides of the housing (see Figs. 9 and 10) The clutch plates 80 and 82 are provided with square openings (see Fig. 10) which receive the square portion of the hub of the pinion BI in such manner that these clutch plates are free to move vertically with respect to the clutch housing and the hub of the pinion, but are constrained to rotate in response to rotation of the pinion. The clutch facings I9 are free to both rotate and move vertically with respect to the pinion 6!, and are also free to rotate with respect to the associated clutch and driving plates, whereby the wear is distributed over both sides of each facing. It Will be seen,

therefore, that relative rotation of the pinion 6| and bevel gear 63 will cause corresponding relative rotation of the driving plates and clutch plates. The driving plates and clutch plates are urged to the relative positions in. which the clutch facings I9 frictionally engage the clutch plates by means of a compressed coil spring 83 which bears at one end against the underside of the clutch plate 82, and at the other end against an outwardly extending annular flange 84 formed on the lower end of a spring seat 84. The spring seat 84 surrounds with some clearance an upwardly extending portion of the hub of the gear 63 and an annular shoulder 62 which is formed on the shaft 62, and is provided at its upper end with an inwardly extending annular flange 84 which overlies and cooperates with the shoulder 62 to limit the lower position with respect to the shaft 62 to which the spring seat is free to move due to the compression of spring 83. The parts are so proportioned that when the flange 84 is engaging the shoulder 62*, the spring will act through the clutch plates and driving plates to bias the pinion 61 to an upper position in which the upper end of its hub engages the underside of the bearing sleeve 68, and it will be seen, therefore, that by adjusting the position of the bearing sleeve the tension of the spring 83 may be varied to thereby vary the force required to slip the clutch, and hence vary the torque which can be transmitted from the bevel gear to the pinion BI through the clutch. The operation of the clutch as a whole will be readily understood from the foregoing description and from an inspection of the drawing without further detailed description.

A bevel gear is also mounted for rotation coaxially with the shaft 20, and is provided on its upper face with a boss which cooperates with the previously referred to thrust washer 28 to prevent vertical displacement of the bevel gear in an upward direction. Vertical displacement of the bevel gear 90 in the opposite direction is prevented by a bushing 9| which cooperates at its upper end with the underside of the bevel gear and at its lower end with a shoulder 20 (see Fig. 4) formed on the shaft 20. The bevel gear 99 meshes With a segmental gear 92 splined to the end of a horizontally extending sleeve 93 (see Fig. 8) which sleeve is rotatably mounted in a ball bearing 94, and in a needle bushing 95 disposed in bearing recesses 96 and 91, respectively, provided in a bearing support 98. The bearing support 98 is bolted to the side of the casting W by means of machine bolts 99, and extends partway into the casting through a suitable opening Illl]. Secured to the outer end of the sleeve 93 is a hand lever I Ill by means of which the sleeve 93, and hence the bevel gear 99 may at times be rotated between two extreme positions.

The spur gear 45 and the bevel gear 90 are adapted to be selectively connected with the shaft 20 by means of a clutch member I05 which is mounted on the shaft 20 for vertical sliding movement, but which is constrained to rotate with the shaft by means of integral splines I05 (see Fig. 13) which cooperate with corresponding splines 20 formed on the shaft 29.

As best seen in Fig. 12, the upper end of the clutch member I95 is provided with a plurality of teeth, two of which 16 and H16 in the particular embodiment illustrated are 62 in length and are spaced 53 apart, and the remaining one of which IlIIi is 47 in length and is spaced 68 from each of the teeth Hi6 and IBB The lower end of the bevel gear 90 is likewise provided with a plurality of teeth, two of which idl and ifi'l (see Fig. 11) are 65 in length and are spaced 50 apart, and the remaining one of which I81 is 50 in l ngth and is spaced 65 from the other two teeth i97 and it'l It follows that the teeth I 56 on the clutch member 135 will fit between the teeth it! on the bevel gear 90 when and only when the space between the teeth ifit and I06 is opposite the tooth ill? on the bevel gear. The parts are so proportioned that this relation will exist when and only when the hand lever i8! and the frog occupy corresponding extreme positions.

Of course, the described dimensions of the teeth on the clutch member 9535 and the bevel gear 96 are not essential, as any other proportioning of parts can be employed which will permit mating of the gear and clutch member when and only when the hand lever iii! and the frog A occupy the proper relative positions.

The lower end of the clutch member 105 is also formed with teeth I08 (see Fig. 13). These teeth are evenly spaced about the end of the clutch member, and are arranged to cooperate with similar teeth H39 formed on the upper end of the spur gear 45, as shown in Fig. 14.

It follows from the foregoing, that when the clutch member I05 is in one longitudinal position on the shaft 2d, the teeth on the lower end of the clutch member Hi5 will connect the spur gear 45 with the shaft 20, whereas, when the clutch member I05 is in another longitudinal position on the shaft 20, the teeth on the upper end of the clutch member I95 will connect the bevel gear 90 with the shaft 2! The clutch member 105 is moved longitudinally on the shaft 20 in order to efiect the desired connection between the spur gear #55 and the bevel gear 90 by means of shifting mechanism comprising a shifter yoke liil which surrounds the clutch member, and which is provided on opposite sides of the clutch member with a pair of rollers Hi that extend into and cooperate with an annular groove 35 formed in the clutch member intermediate its ends. The shifter yoke i i6 is pivotally attached at one end by means of a pin H2 to a floating fulcrum block H3, and the floating fulcrum block, in turn, is pivotally attached by means of a pin H i to an eye bolt H5. The eye bolt H5 extends with considerable clearance through an opening i if: provided in a supporting casting I H, and is provided on its outer end with a compressed coil spring H8, a spring seat H3, and a castellated nut i28. The spring H8 bears at its outer end against the spring seat H9 and at its inner end against the inner end of a recess Hl formed in the casting H1, and serves to constantly bias the eye bolt, and hence the fulcrum block H3 toward the left, as viewed in Fig. 8, to a position in which rounded bearing surfaces H3 and H3 formed on the bottom and top of the fulcrum block engage rounded seats H! and H7 provided on the casting Hi. It will be apparent that the force with which the fulcrum block is held into engagement with the rounded seats i i! and i il 'will depend upon the compression of the spring H8, and that the compression of the spring H8 may be varied by screwing the castellated nut I29 to difierent positions on the eye bolt H5. The nut iii} may be locked in its adjusted position by means of a cotter key 120 in the usual and well-known manner. The casting H1 extends into the casting M through a suitable opening Elli provided in the side wall of the casting M and is secured to the casting M by means of suitable bolts E22. The right-hand end of the shifter yoke iiil, as viewed in Fig. 8, is formed with an elongated slot mi and cooperating with this slot is a rounded pin 123 which is formed on the inner end of a shaft lZQ in eccentric relation with respect to the axis of the shaft. The shaft i25- extends through, and is rotatably mounted in, the sleeve 93, and is provided at its outer end with a selector lever i25 by means of which the shaft 525 may at times be oscillated.

The operation of the shifting mechanism is as follows: Normally, the selector lever i125 occupies the extreme position in which it is shown in the drawings, which is the position for motor operation, and under these conditions, the pin W3 is at the lowest point in its path of movement. When the pin occupies this position, it engages the underside of the slot us in the shifter yoke iii), and the parts are so proportioned that if the teeth iEit on the lower end of the clutch member W5 are then in position to enterthe recesses between the teeth tile on the spur gear 45, the yoke iii will be rotated downwardly about the pivot pin H2 as a fixed pivot to its lowermost position, and will act through the rollers i H to move the clutch member Hi5 downwardly to, and hold it in, its lowermost position in which the teeth H18 on the clutch member mesh with the teeth MP9 on the spur gear. If, however, the teeth on the lower end of the clutch member do not align with the recesses between the teeth iilil on the spur gear when the pin in on the shaft iii l occupies lowermost position, so that the clutch member is prevented from moving to its lowermost position by engagement of the two sets of teeth at their confronting ends, the engagement of the pin H23 with the bottom of the slot iifi will cause the shifter yoke to rotate in a clockwise direction, as viewed in Fig. 8, about the rollers i i i as fixed pivots, and this rotation, in turn, will cause the fulcrum block M3 to rotate in a counterclockwise direction about the surface iii as a fulcrum, and will thus cause the spring iii to become compressed beyond its initial compression. It will be seen, therefore, that under the conditions last assumed, the spring H8 will act through the fulcrum block M3 and shifter yoke to bias the clutch member i135 to its lowermost position, with the result that as soon as the spur gear 45 is rotated by the motor 33 to the position in which the teeth iii? on the clutch member align with the recesses between the teeth M9 on the spur gear .5, the parts will immediately snap to the positions in which they are shown in Fig. 8. When the parts occupy these positions, the spur gear 45 is operatively connected with the switch actuating shaft 21) so that the apparatus is then in condition for operation of the frog by the motor B. At such times, the bevel gear 90 is disconnected from the switch actuating shaft 20, with the result that the hand lever tilt is disconnected from the frog. In order to disconnect the motor from, and connect the hand lever with, the frog, the selector lever i 25 is rotated through an angle of approximately 210 from the position shown, thereby rotatin the pin E23 through a corresponding angle. This rotation of the pin I23 causes the shifter yoke to rotate in a counterclockwise direction, as viewed in Fig. 8, and hence causes the clutch member i 85 to move upwardly on the shaft 20. When the clutch member I $5 is moved upwardly under these conditions, if the position of the switch and the hand lever iiil then correspond, so that the teeth Hi5 on the clutch member align with the spaces between the teeth Mil on the bevel gear 90, the shifter yoke ill will rotate about the pin H2 as a fixed pivot, and will thus move the clutch member I to its upper extreme position in which the teeth on the clutch member and the teeth on the bevel gear mesh. The bevel gear 96 will then be connected with the shaft Zll, so that the switch may be operated between its two extreme positions by swinging the hand lever between its two extreme positions. If, however, the position of the switch and the hand lever do not correspond when the selector lever I 25 is rotated to the hand-throw position, so that the teeth Hill on the bevel gear 9t are opposite the teeth Hit on the clutch member, as soon as the clutch member has been moved upwardly a comparatively short distance, the flat ends of the teeth Hi5 on the clutch member will engage the flat ends of the teeth Mil on the bevel gear and will thus prevent further upward movement of the clutch member, with the result that the balance of the movement of the selector lever to the hand-throw position will cause the shifter yoke I I6 to rotate in a counterclockwise direction about the axis of the rollers ill, and will thus cause the fulcrum block M3 to rotate about the rounded surface M3 thereby causing the spring M8 to become compressed beyond its initial compression. It will be apparent, therefore, that under these conditions, the hand-throw lever iii! will not become connected with the switch until the hand lever is moved to the position corresponding to the position of the switch, at which time the energy stored in the spring H8 will complete the upward movement of the clutch member, thereby causing the teeth on the clutch member to mesh with the teeth on the bevel gear tit, and hence permitting manual operation of the switch in the manner previously described.

When it is desired to restore the apparatus to condition for operation by the motor, the selector lever 525 is restored to its normal position in which it is shown in the drawing. The operation of the apparatus under these conditions is just the reverse of that described hereinbefore, and will be readily understood from an inspection of the drawings without describing it in detail.

It will be apparent, therefore, from the foregoing that with apparatus embodying our invention, the selector lever 325 may be thrown to its operating position for either hand or motor operation of the frog regardless of whether there is an agreement or disagreement between the position of the frog and the position of the operating mechanism. It will also be apparent that if the hand lever is thrown to the operating position for either hand or motor operation of the frog when a disagreement between the position of the frog and the position of the operating mechanism exists, then when the position of the operating mechanism is brought into agreement with that of the frog, the desired connection between the frog and the operating mechanism will be automatically effected.

Associated with the hand-throw lever MM and the selector lever H5 is a mechanism D including means for locking the levers against movement by unauthorized persons and means for interlocking the levers in such manner that the hand-throw lever cannot be operated unless the selector lever occupies the hand-throw position. This mechanism forms no part of our present invention, and may, for example, be similar to that described and claimed in Letters Patent of the United States No. 1,887,376, granted to G. V. Jefferson and E. G. Little, on November 8, 1932, for Railway switch operating apparatus. Inasmuch as the mechanism D forms no part of our present invention, it is deemed unnecessary to describe it in detail herein.

It should be pointed out that the parts are so constructed that the bearing support 98 and the supporting casting ill can be reversed to enable the switch machine to be assembled for either a right-hand or a. left-hand installation.

The motor B may be of any suitable type, and may have any desired construction which will provide the proper operating characteristics. As here shown, this motor is a direct current motor and comprises the usual armature I30 and field coils 93! disposed in an enclosing casing I32, one end of which is provided with a removable cover P33 through which convienient access to the commutator and brushes, as well as to a magnetic brake E which is disposed in one end of the casing i352 may be had. The shaft 65 which carries the armature ltd is mounted in ball bearings, in the usual manner, and one end thereof projects through the one end wall of the casing E32 and carries the previously referred to bevel pinion (iii. The motor B projects partway into the casting t l through an opening I34 in the end of the casting in such manner that the commutator and brushes are disposed wholly within the casting M and the motor is secured to the end wall of the casting M by means of tap bolts I35, some of which pass through clearance holes in the end wall and are screwed into tapped holes provided in a flange I36 formed on the casing 832 at or near its medial portion, and the remainder of which bolts pass through clearance holes provided in the flange I36 and are screwed into tapped holes provided in the end wall of the casting. A U-bolt I3? is secured to the top of the casing I32 outside of the casting Mi and this U-bolt serves as a convenient means for securing one end of the cover MW in place and also as a means for lifting the motor when assembling it to or disassembling it from, the switch machine, as well as a means for lifting one end of the switch movement as a whole when the motor has been assembled to the remainder of the mechanism.

The motor brushes Mi! are disposed in brush holders i 'il which are secured by means of screws to an arcuate insulating plate M3. The insulating plate M3, in turn, is secured by means of tap bolts l ltto a mounting strap I i-5. The mounting strap is provided with ears I45 containing arcuate slots Hi1, and is attached to a supporting bracket M9 by means of screws i5Il which pass through the arcuate slots Ml and are screwed into tapped holes provided in the bracket i 19. The arcuate slots t ll are so disposed that when the screws H56 are loosened, the strap I45, insulating plate M3 and brush holders as a unit may be rotated through a limited angle to enable the brushes to be shifted to the proper positions to provide sparkless commutation. The upper end of the strap M5 is formed with a lug it! provided with a hole Q52 and after the brushes have been adjusted to the proper positions and the screws l5!) have been tightened, a hole is drilled in the bracket I49 in alignment with the hole I52, and a dowel pin I53 is driven into the two aligned holes to prevent the brushes from shifting in the event that the screws I50 subsequently become loosened. The supporting bracket I49 is secured to the opposite sides of the casing I42 of motor M by means of tap bolts I54, as shown in Figs. 17 and 18.

It should be particularly pointed out that with electric switch machines as they have heretofore generally been constructed, trouble has been experienced in certain exposed locations under adverse weather conditions due to accumulations of frost on the motor commutator. With the motor constructed and arranged in the manner just described, due to the relatively large amount of air space which is provided within the casing I32 at the commutator end of the motor, and to the fact that the commutator is enclosed both within the motor casing and also within the gear box casting Ma, the tendency for frost to collect on the motor commutator has been practically eliminated.

The previously referred to magnetic brake E comprises a brake disk I51 secured to a die casting I58 which is mounted for longitudinal sliding movement on the armature shaft 65, but which is constrained to rotate with the armature shaft by means of a feather key I59. One side of the brake disk I5! cooperates with a brake lining I80 secured to a stationary brake shoe I6I, and the other side of this brake disk cooperates with a brake lining I62 secured to a movable brake shoe I83. The stationary brake shoe I6I is formed with an externally screw threaded hub I 84, which hub is adjustably screwed into the inner end of the bearing opening I65 in the end wall of the motor casing I32. After the stationary brake shoe has once been adjusted to the desired position, it is subsequently maintained in this position by means of a locking screw I66 which is screwed through a threaded hole formed in the end wall of the motor casing, and which projects at its inner end into one of a plurality of holes I 51 provided in the outer face of the stationary brake shoe I6I in a position to receive the screw. The movable brake shoe I63 is provided with a hub I68 which is slidably mounted on a tubular support I69 formed on the bracket I49 in concentric relation to the shaft 65. Surrounding the hub I68 and the tubular support I69 between the movable brake shoe and the support is a compressed coil spring I10 which con stantly biases the movable brake shoe and the brake disk I51 toward the stationary brake shoe to braking positions in which the two brake linings I60 and I62 frictionally engage the brake disk I51. It will be apparent that when the brake linings are engaging the brake disk, rotation of the motor armature will be resisted.

The magnetic brake E also comprises an operating yoke I1I which is pivotally suported adjacent its upper end on a rod I12 mounted in spaced lugs I13 provided on the bracket I49, and the arms I1I and I1I of which extend downwardly past the opposite sides of the movable brake shoe I63 and are operatively connected intermediate their ends with the brake shoe by means of recesses I1I which are formed in the arms HI and HP, and which cooperate with diametrically opposite laterally projecting lugs I15 provided on the brake shoe at its outer edge. Secured to the lower ends of the arms I1I and I1I are armatures I10 and I11, respectively, which cooperate with magnets F and F located in the bottom of the motor casing. As will be seen from an inspection of Fig. 17, the magnets F and F are of the ironclad type, and each comprises a suitable cup-shaped shell I 18 formed integral with the motor casing, a central core member I19 secured at one end to the shell, and a winding I80 which surrounds the associated core member within the associated shell.

A tension spring IBI is hooked at one end onto a lug I82 provided on the one end wall of the motor casing I 30, and the other end of this spring is secured to a bolt I83 which extends with clearance through a hole I1I provided in a channelshaped offset portion I1I formed on the upper end of the operating yoke I1I. An adjusting nut I85 is screwed onto the outer end of the bolt I83, and formed on the inner end of this nut is a wedge-shaped surface I88 which cooperates with a notch I'I'I provided in the adjacent face of the offset portion, whereby when the nut I85 has been rotated to any position in which the wedge-shaped surface I86 aligns with the notch, the tension of the spring I8I will act to hold the wedge-shaped surface in the notch, and will thus prevent the nut from becoming unscrewed and destroying the adjustment. The spring I8I exerts a force on the operating yoke I'II which rotates the yoke in a clockwise direction, as viewed in Fig. 16, about the rod I12 to the position in which the recesses I'II on the arms HI and I1 I receive the lugs I15 on the movable brake shoe I63, and it will be seen, therefore, that the spring I8! serves to take up any clearance surrounding pin I12 in such a way that the air gap between the armatures E16 and I1: and the associated magnets F and F is held to the minimum. It will further be seen that due to the connection between the yoke I 1| and the movable brake shoe I63, the force due to the spring I 8! opposes the force which is exerted on the movable brake shoe by the spring I10, and it follows, therefore, that by adjusting the nut I85 to different positions, the resultant force which is exerted on the movable brake disk I51, and hence the braking force exerted by the brake, may be quickly and conveniently varied to any desired value within the limits of the apparatus.

The windings I80 of the two magnets F and are adapted to be connected in series in the operating circuit for the motor M in such manner that the motor current will flow in these windings, and it will be apparent that whenever the motor is deenergized, the spring I10 will actuate the brake to its braking position, and will thus cause the brake to oppose rotation of the motor armature. When, however, the motor becomes energized, the magnets F and F will attract the armatures I16 and I11, and will thus rotate the operating yoke I1I in a clockwise direction as viewed in Fig. 16. This rotation will act through the recesses I1I and lugs I15 to slide the movable brake shoe I63 toward the left, in opposition to the bias of the spring I10, to a position in which the pressure of the brake linings against the brake disk I51 is removed, thereby releasing the brake, and hence permitting the motor armature to rotate without opposition from the brake.

It will be readily understood that when the armatures I16 and I11 are moved to their attracted positions, the reluctances of the flux paths forthe fluxes set up by the energized windings will be considerably reduced due to the decreased air gaps between the armatures and the magnets, and that, as a result, the current required to hold the armatures I16 and I11 in their attracted positions will be considerably less than that required to move them to their attracted positions. It is desirable that the magnets should not' become energized at current values below that flowing in the motor circuit under starting conditions, in order to prevent improper operation of the switch machine due to stray currents which might be supplied to the motor, and it follows that by properly adjusting the air gaps which exist between. the armatures and the magnets when the armatures occupy their deenergized positions, the characteristics of the brake may be so adjusted that it will be necessary for a current to flow in the windings I89 corresponding to the current which flows in the motor under normal starting conditions in order to release the brake, but that the brake will be maintained in its released position by a reduced current which is equal to the normal operating current for the motor. The necessary adjustments to accomplish this desired result may be made by unscrewing the locking screw I56 and rotating the stationary brake shoe I6I in one direction or the other. This rotation will move the stationary shoe in an axial direction toward or away from the frame I99, which movement, in turn, will cause a corresponding movement of the movable brake shoe E93, thereby causing the operating yoke i ii to rotate to a new position in which the armatures H and H! are closer to, or farther away from, the magnets, as the case may be. After the necessary adjustment has been made, the stationary brake shoe may again be locked against rotation by means of the locking screw I56.

One advantage of a magnetic brake embodying our invention is that due to the fact that it moves to its braking position as soon as the motor becomes deenergized, it tends to reduce the shock upon the switch operating mechanism as it comes to rest following a reversal of the switch.

Another advantage of a magnetic brake embodying our invention is that it is effective to prevent creepage of the mechanism due to track vibrations when the motor is deenergized, which insures that the switch operating mechanism will not become unlocked due to creepage in the event of a power failure.

A further advantage of a brake embodying our invention is that adjustments which may be necessary due to wear of the brake linings, and to adapt the brake to different operating conditions may be quickly and conveniently made.

Resiliently supported in the right-hand end of the casting M of the switch machine is an inner casing I99 which is adapted to house an electromagnetic control device for controlling the switch machine. This control device forms no part of our present invention, and may, for example, comprise a polar relay of well-known construction. Inasmuch as this control device forms no part of our present invention, it is deemed to be unnecessary to describe it in detail herein.

Mounted in the right-hand end of the casting M above the lock rods L and L and the slide bar N is a circuit controller 6- which also embodies our invention. As best seen in Figs. 20 to 25, this circuit controller comprises a suitable supporting framework I99 provided with end members E99 and @99 and having adjustably mounted in its sides aligned bearings I9I and I92 in which a horizontal camshaft I93 is journaled. The camshaft I93, which is of rectangular cross section except for a rounded portion at each end which fits into the associated bearing, is adapted to be rotated or oscillated in response to the longitudinal movements of the slide bar N, and for this purpose the shaft I93 has fixed thereto a gear wheel I94 which meshes with an intermediate idler gear I95 driven by the rack teeth provided on the upper face of the locking dog ll of the slide bar N. The idler gear I95 is journaled on a pin I96 (see Figs. 23 and 24) mounted in a depending portion I91 of the frame I90. Mormted on the camshaft I93 on opposite sides of the gear wheel. I94 are a plurality of driving collars of insulating material, each designated by the reference character l98 with a suitable distinguishing exponent. Each driving collar I98 is provided with a square hole which has a sliding fit on the camshaft I93, and as clearly shown in Fig. 24, each driving collar comprises a comparatively narrow web and peripheral flange extending in each direction from the outer edge of the web. A portion of the peripheral flange of each driving collar is tapered, and the tapered portion is provided with serrations or teeth (not shown) around its entire circumference. Each driving collar I98 carries a contact segment of electroconductive material designated by the reference character 999 with the same distinguishing exponent as the exponent for the reference character of the associated collar. Each contact segment I99 is in the form of the segment of a ring, the bore of which is tapered to fit the tapered portion of the periphery of the associated driving collar. The bore of each driving collar is also provided with serrations or teeth (not shown) which match the teeth on the periphery of the insulated driving collars. Each contact segment I99 cooperates at its periphery with two contact fingers designated by the reference characters 209 and 20! respectively, with the same distinguishing exponent as the reference character for the associated contact segment. For example, the contact segment I99 cooperates with the contact fingers 299 and 2i to at times close a contact 2IJ9 --I99 --29I The periphery of each contact segment may have any desired length, and due to the mating teeth on the driving collars, the segment may be turned to any desired position relative to the camshaft I93. As here shown, the parts are so proportioned and the contact segments are of such length and are so disposed on the shaft I93 that the contacts Z99 I99= 2ilI and 290 i99 29I will be closed at all times except when the slide bar N is in the extreme position in which it looks the switch points in their normal positions in which they are shown in Fig. l, and that the contacts 2!l!]-I99--2Ii and 2I)il I99 20I will be closed at all times except when the slide bar N is in the extreme position in. which it locks the switch points in the positions reverse to that in which they are shown in Fig. l. The contacts 299 I99=*25I 299 -I99 29I 299I9929I, and 2IlJ --I99' 2EH may be used in a well-known manner to control the cir cuits for the motor M, or for any other desired purpose.

The circuit controller also comprises a pair of contact fingers 295 which are connected together for simultaneous movement by an insulating bridge 299 and a pair of contact fingers 295 which are connected together for simultaneous movement by an insulating bridge 206. The fingers 205 and 295 are biased by their own resiliency to lower positions in which they engage associated lower stationary contact members 22'! and 2511 to close a pair of contacts 2!)5= 297 and a pair of contacts 205 -201 but are adapted to be at times moved upwardly, by means of a point detector mechanism which we will now describe, to upper positions in which they engage an upper stationary contact member 2139 to thereby close a contact 2U5 -2B9205 The point detector mechanism is controlled jointly by the slide bar N and by a pair of detector rods 1-1 and I-I which are slidably mounted in the casting W of the switch machine for movement in directions parallel to the operating rod 0, and in the form here shown comprises a detector plate 2!! and a driving plate 212. The detector plate 2H is slidably mounted on machined surfaces 192 (see Fig. 21) formed on the end members I90 and [90 of the frame 190, for movement at right angles to the camshaft 93 in parallel spaced relation thereto, and is guided laterally by means of two rollers 213 which are mounted on depending pins secured to the detector plate, and which ride in guideways 190 formed in the end members 190 and 190 Vertical displacement of the detector plate is prevented by a pair of hold-down pieces 214, which hold-down pieces are fastened to bosses formed on the end members 190* and 1911 adjacent the opposite corners of the detector plate, and which project over the upper surface of the detector plate with some clearance. Mounted on the underside of the detector plate are four rollers, two of which 2l5 and 2H5 cooperate with the point detector rod I-I (see Fig. 21), and the remaining two of which 2I5 and 21G cooperate with the point detector rod H The detector rods H and H are adjustably connected by means of connecting rods 2|l and 2!? (see Fig. 1) and point lugs 2I8 and 2l8 with the front rods 1 and l respectively, and it will be apparent, therefore, that any movement or" the switch points will cause corresponding longitudinal movement of the detector rods. Each of the detector rods is provided at the end which is connected to the associated connecting rod with a reduced portion 220 (see Figs. 21 and 31), and adjustably mounted on this reduced portion is a sleeve 22! which forms, with the portion of the detector rod which is not reduced, an annular recess 222. The parts are so adjusted that the recess 222 in the detector rod 1-1 will align with the roller 2i5 and the recess 222 in the detector rod l-I will align with the roller 2I6 when and only when the switch points occupy their normal positions in which they are shown in Fig. 1; and that, the recess 222 in the detector rod I-I will align with the roller 216 and the recess 222 in the detector rod H will align with the roller 2| 5 when and only when the switch points occupy the extreme position opposite to that in which they are shown in Fig. 1. It is obvious that when the recesses 222 in the detector rods l-I and H align with the rollers 2 I5 and 215 the detector plate 2 is free to move to the left to a normal position in which the rollers 2&5 and 2i6 enter the associated recesses, in which position the detector plate is shown in the drawings, and that when the recesses 222 in the detector rods H and I-I align with the rollers 2W and 2l5 the detector plate 2!! is then free to move toward the right to a reverse extreme position in which the rollers 2l6 and 25* enter the associated recesses. The parts are so proportioned that when either one of the recesses is out of alignment with both of the associated rollers, these rollers will cooperate with the associated detector rod to force the detector plate to, and hold it in, a position approximately midway between its two extreme positions.

In order to allow for slight variations which are likely to occur between the position of the switch points and the position of the switch machine, due, for example, to the shifting of the ties, without interfering with the free operation of the point detector rods, and at the same time permit a limited amount of movement between the connecting rods and the detector rods to prevent binding of the detector rods in their guideways due to the necessary movement of the connecting rods caused by the movement of the switch points between their two extreme positions, we prefer to secure each of the detector rods to the associated connecting rods in the manner shown in connection with the detector rod H and connecting rod 2W shown in Fig. 31. Referring to Fig. 31, as here shown, an upturned portion 211 of connecting rod illl is provided with an eye 2 H which loosely receives a screw threaded portion 2l9' of the connecting rod H with some clearance. One side of the eye 2H is formed with a hexagonal recess 2H having a concave inner surface, and the other side of the eye 2H is provided with a convex surface 2H which is parallel to the concave inner surface of the eye. A nut 223 is screwed onto the threaded portion 289 of the connecting rod H on the side adjacent the recess 2l'l and this nut fits loosely into the recess 2H and is provided at its inner end with a convex surface having the same radius of curvature as the contiguous concave surface of the eye. Mounted on the screw threaded portion of the rod on the other side of the eye MP is a nut 224 provided on the side adjacent to the eye with a concave surface having the same radius of curvature as the contiguous convex surface of the eye. The nuts 223 and 22 1 are so adjusted that relative longitudinal movement of the connecting rod and detector rod is prevented, but that, a limited amount of angular movement of these two rods is permitted, and the nuts are then looked in place by a jam nut 238 which is screwed onto the threaded portion 259 of the detector rod and which engages the outer face of the nut 224 The driving plate 252 is slidably mounted in guideways 225 provided on the detector plate 2 H on opposite sides of a rectangular opening 226 formed therein, and is arranged to be moved be-- tween an intermediate and two extreme positions in response to the movement of the slide bar N between its intermediate and two extreme positions, by means of two cams 227i and 228 which are mounted on the cam-shaft i925 on opposite sides of the gear wheel we, and which cooperate with two rollers 229 and 232 secured to uprights 23! formed on the driving plate. A driving arm 232 (see Fig. 22) is pivotally attached at one end to the detector plate 2!! by means of an upstanding pin 233, and is provided intermediate its ends with a rectangular slot 23% which slidably receives a cross-head block 235 pivoted on an upstanding pin 236 secured to the driving plate. The free end of the driving arm 232 carries a roller 232 which cooperates with a radial notch 23! provided in an operating arm 232. The operating arm 23! is pivoted at one end on a pin 238 secured to the detector plate 2i I, and is operatively connected at the other end with a tension spring 239 which is stretched between the arm and a projecting lug 2% formed on the detector plate. The tension of the spring 239 is such that under normal operating conditions the roller 232 will remain in the notch 231 and it will be apparent that as long as the roller remains in this notch the detector plate will move in response to, and in unison with, the driving plate 261, but that, if the roller 232 is forced out of the notch Z3? in the arm 23?, the detector plate can then move independently of the driving plate, or vice versa.

An L-shaped latch dog 242 is pivotally attached intermediate its ends to the detector plate 21!, and is biased by means of a coil spring 253 to a latching position in which a notch 262 in the arm receives a latch lug 2M formed on the operating arm 23"! provided the operating arm is then moved outwardly to the position which it occupies when the roller 232 is forced out of the notch 23% in the arm 23?. The spring 243 abuts at one end against an upstanding lug 2 52 formed on the short arm of the latch dog 242, and at the other end against an upstanding lug 244 formed on a latch arm Md. The latch arm 244 is pivotally mounted at one end on the pin 238 underheath the operating arm 23'], and is constantly biased by means of the compressed spring 243 to a latching position in which a notch 2% formed in its outer side is adapted to receive a latch catch 255 secured to the frame I Bil. The tension spring 239 is somewhat stronger than the compression spring M3 and provided on the operating arm 232 is a vertically offset laterally projecting portion 231 which cooperates with the lug 2M at its outer side to prevent the latch arm from moving to its latching position except when the roller 23%. is forced out of the notch 237 in the operating arm 231'. The parts are so proportioned that the notch 2M will align with the latch catch 2415 when and only when the detector plate 2!! occupies its intermediate position.

As will appear hereinafter, it is desirable to be able to at times prevent the latch dog from moving to its latching position, and for this purpose the latch dog is provided with a hole 2H2 which, when the latch dog is rotated in a counterclockwise direction through a slight angle from the position shown to a position in which the lug 23? is clear of the side of the latch dog 242, aligns with a tapped hole 246 provided in the detector plate. The hole 246 is adapted to receive a screw will, and it will be apparent that when the screw 24?! is in place in the two aligned holes, the latch dog 2:22 will be held in a fixed position in which it is out of engagement with the latch lug 23'? on the operating arm 23?. In order that the screw 24'! will always be available, the detector plate is provided with a second screw threaded hole 348 (see Fig. 21) in which the screw 2 51 is normally kept, and the latch dog 262 is provided with an arcuate slot 242 which, when the screw 24? is in the hole 2%, receives the head of the screw with sufiicient clearance to permit the normal intended movement of the latch dog.

The upper side of the detector plate 2H is provided on opposite sides of the driving plate 212 with rack teeth 2! l and 21t respectively, which mesh with gear segments 2511 and 258 formed on cam members 25 l and 25 The cam members 25 i and 25E are journaled on bushings 252 and 252 which are mounted on the camshaft Hi3 on opposite sides of the cam members 227 and 228, and are maintained in the proper longitudinal positions to engage the rack teeth by means of annular flanges 253 and 253 formed on the bushings, and washers 254 and 254 which are interposed between the bushings and the adjacent driving collars lQS and N8 The cam member 25t is provided, in addition to the gear segment 25E! with an upwardly extending cam segment 255 which is adapted to cooperate with a roller 256 carried by the insulating bridge 28%, and the cam member 256 is likewise provided, in addition to the gear segment 25%, with an upwardly extending cam segment 255 which is adapted to cooperate with the roller 256 carried by the insulating bridge flilii The upper portion of the cam segments 255 and 255 as here shown, are curved, and are slightly more than twice as wide as the rollers 258 and 25t Formed in the upper surface of the cam segment 1255 adjacent the opposite ends therein in laterally spaced relation are two recesses or notches 25t and 258 (see Figs. 22 and 23) of such length and size that when either one of these notches is in alignment with the roller 256*, the contact fingers Eilfi will be free to move, due to their bias, to their lowermost positions. The roller 256 is loosely mounted on a laterally extending pin 259* which is slidably mounted at its opposite ends in vertical slots 26W. formed in depending lugs 26t provided on a roller support 262 and the roller support 262*, in turn, is secured to the insulating bridge 265 by means of a tap bolt 263 (Fig. 23). The tap bolt 2&3 extends downwardly through an elongated vertical slot 2M (Fig. 20) formed in the bridge 206*, and is screwed at its lower end in a tapped hole 265* provided in the roller support. Formed on the upper side of the roller support 262 are serrations 25t which cooperate with serrations 26'! formed on the underside of the bridge 20t in such manner that by loosening the bolt 2&3 the roller supports may be shifted longitudinally relative to the fingers 295 through a limited distance to take care of manufacturing variations in the assembled parts, and to obtain the proper timing of the contacts. The pin 259 is of sufficient length, and the parts are so proportioned that when the pin is at the lower end of the slots 2%, the roller 256 can be slid longitudinally along the pin from a position in which it will enter the notch 25G in the cam segment 2255 when this cam segment is rotated to one extreme position, to a position in which it will enter the notch 251* in the cam segment 255 when the cam segment is rotated to its other extreme position. When, however, the pin is in the upper ends of the slots 260', the roller 253 is held in the proper position to cooperate with the one notch or the other, as the case may be, by a vertically disposed wall 268 (Fig. 24:) which is provided on the roller support for this purpose. The upper end of the wall 2'58 extends into a groove if-35t formed in the underside of the insulating support 20%? and acts as a guide to position the roller sup port laterally with respect to the insulating bridge. The parts are further so proportioned that when the roller 255 is out of both of the notches iiiii and 258 the fingers 2135* will be lifted by engagement of the roller with the upper surface of the cam segment 255 to their upper positions. The cam segment 255 is similar in construction to the cam segment 255 and the parts of this cam segment are designated by the same reference characters as the corresponding parts of the cam segment 255 but with the exponent an added thereto in place of the exponent b. The means for securing the roller 25B to the insulating bridge 258" is likewise similar to the means for securing the roller 25G to the bridge 2655 and the parts of these two means are designated by the same reference characters with suitable distinguishing exponents.

The operation as a whole of the portion of the circuit controller thus far described is as follows: As shown in the drawings, the switch points occupy their full normal positions and are locked in these positions by the slide bar N, and under these conditions, the camshaft H53 is rotated in a counterclockwise direction, as viewed in Fig. 23, to what we shall term its normal extreme position, so that the motor control contacts 2v'ifil992fll and 2Bfi I99 -29i are closed, and the motor control contacts 2E5 -l99 -2tii and 2fi0 -i99 2ill are open. Furthermore, under these conditions, the driving plate 2! i is moved to its left-hand or normal extreme position by the cam 22'! and roller 223, and since the notches 222 and the point detector rods H and I-i are then in alignment with the rollers 215 and ME, so that the detector plate 22 i is free to move to its left-hand extreme position, the detector plate is moved to its left-hand or normal extreme position through the medium of the driving arm 232 and the operating arm 23']. When the detector plate 2i i occupies its normal extreme position, the cam members 252 and 252" are rotated in a clockwise direction to their normal extreme positions, and the rollers 25%: and 256 are disposed in such positions on the associated pins 259 and 252 that, under these conditions, the contacts 2'B5 2ol are open and the contacts 2 35 -281 are closed We will now assume that with the parts in the positions just described, the switch machine is operated to move the switch points from their normal positions to their reverse positions. During the first or unlocking part of the resultant movement of the slide bar N, no motion of the switch points takes place for the reasons pointed out hereinbefore, but during this movement, the camshaft IE3 is rotated in a clockwise direction to its intermediate position, and this movement causes the contacts 2G2 -!99 2Bl and Hill WW -251* to become closed. This movement also causes the driving plate 2 l2 to move to its intermediate position d is to the coaction between the cam 228 and the roller 23%, and this latter movement, in turn, moves the detector plate 25! to its intermediate position, thereby causing the cam members 255 and 25i to rotate to their intermediate positions. The rotation of the cam members 251 and 255 to their intermediate positions causes both rollers 25s and 25% to ride on the high portions of the cam members, thus causing the contacts 235* and 2t? to bccome opened and contact 2tl5 2l382l5 to become closed. The movement of the detector plate 2H to its intermediate position also moves the rollers 215 and 216 out of the recesses in the point detector rods H and H and it will be apparent, therefore, that during the movement of the switch points to their reverse positions, all of the rollers 2551, 215 Zit and 255' are clear of the point detector rods so that the resultant movement of the point detector rods will not cause any movement of the detector plate. After the switch points have reached their full reverse positions, the final or looking movement of the slide bar N which then takes place will rotate the camshaft 193 in a clockwise direction, as viewed in Fig. 23, from its intermediate to its reverse extreme position, thereby opening contacts 200-l99--2ti and 250 l99 2ill This rotation of the camshaft I93 will also act through the cam 228 and the roller 230 to move the driving plate 2l2 to its reverse extreme position, and since the notches 222 in the point detector rods will then be in alignment with the rollers 216 and 2l5 so that the detector plate is free to move to its reverse extreme position, the move ment of the driving plate 2i2 will act through the driving arm 232 and the operating arm 23'? to move the detector plate to its reverse extreme position in which the rollers 216 and 215 are disposed within the aligned notches 222. The movement of the detector plate will rotate the cam members 25 I and 25! in a counterclockwise direction, as viewed in Fig. 23, from their intermediate to their reverse extreme positions, and when the cam member 25l reaches its reverse extreme position, the roller 255 will enter the notch 258 and will thus allow the contact fingers 225 to drop to their lowermost positions, thereby opening contact 2il5 -2fi9-285 and closing contacts 295 20l It should be noted that inasmuch as the driving and detector plates move in unison in the manner just described during reversal of the switch points by the switch machine, all parts of the latch mechanism will remain in the relative positions shown under these conditions, and the latch mechanism does not, there fore, have any effect on the operation of the circuit controller under these conditions.

If, after the switch points have been moved to their reverse extreme positions, the SWltCh ma" chine is subsequently operated to restore the switch points to their normal positions, the operation of the circuit controller will be exactly the reverse of that just described, and it is believed, therefore, that this operation will be apparent from the foregoing and from an inspection of the drawing without further detailed description.

-We will now assume that with the parts in the positions in which they are shown in the drawing, the detector rod H is moved upwardly, due. for example, to a train trailing the switch. This movement will force the roller 2E5 out of the recess 222 in the detector rod, thereby forcing the detector plate 2!! toward the right, as viewed in Fig. 23., to its intermediate position, and since the driving plate 2! 2 is now held stationary by the cam 22'? and the roller 229, the driving arm 232 will be rotated in a counterclockwise direction, as viewed in Fig. 22, about the pin 233 an amount which is approximately twice the distance that the detector plate is moved. This rotation will force the roller 232 out of the notch 23% in the operating arm 23? and onto the curved side of this arm adjacent the notch, thereby causing the operating arm to rotate in a counterclockiz ise direction, as viewed in Fig. 22, about the pin 238, and hence causing the spring 239 to become stretched beyond its initial tension. The operating arm 23'! on each side of the notch 23% has a curved surface having a radius whose center is the pin 233, so that when the roller 232 engages this surface, the force due to the spring 23% does not tend to drive the detector plate 2H longitudinally. The counterclockwise rotation of the operating arm 23'! under these conditions moves the lug 231 upwardly, as viewed in Fig. 22, to a position in which it aligns with the notch 3:32 in the latch dog 242, whereupon the latch dog rotates in a clockwise direction, as viewed in Fig. 22, due to the bias of the spring 243, to its latching position in which the notch 222 receives the lug 231 thereby causing the operating arm to be subsequently retained in its displaced position. 

